There has been known a device for detecting linear device values distributed in a matrix. Patent Literature 1, for example, discloses a touch sensor device (contact detecting device) for detecting distribution of capacitance values of a capacitance matrix Cij (i=1, . . . , M and j=1, . . . , L) formed between M drive lines and L sense lines. The touch sensor device operates in accordance with a scanning detection method; specifically, the touch sensor device sequentially selects one of the drive lines and thus detects respective values of linear devices connected to the drive line selected.
Patent Literature 2 discloses a capacitance detecting circuit which (i) in driving a plurality of drive lines, switches between a first drive line group and a second drive line group on the basis of a time series code sequence, (ii) outputs a measured voltage obtained by converting, into an electric signal, a sum total of respective currents across capacitances, connected to sense lines, at a plurality of intersections of driven drive lines with the sense lines, and (iii) performs a product-sum operation of such a measured voltage and the code sequence for each sense line so as to find a voltage value corresponding to a capacitance at each intersection.
Patent Literature 6 discloses a capacitance distribution detection circuit that detects a distribution of capacitance of a plurality of capacitors, which capacitors are each formed at intersections of a plurality of first signal lines with a plurality of second signal lines. As shown in FIG. 1 of Patent Literature 6, a positional relationship of (i) drive lines for driving the touch panel with (ii) sense lines for reading out signals from the touch panel is fixed with respect to the touch panel.
FIG. 27 is a block diagram illustrating a configuration of a conventional touch sensor system 91. FIG. 28 is a schematic view illustrating a configuration of a touch panel 93 provided in the touch sensor system 91. The touch sensor system 91 includes the touch panel 93 and a capacitance distribution detection circuit 92. The touch panel 93 includes drive lines HL1 to HLM arranged parallel to each other in a horizontal direction, sense lines VL1 to VLM arranged parallel to each other in a vertical direction, and capacitors C11 to CMM each formed at intersections of the drive lines HL1 to HLM with the sense lines VL1 to VLM.
The capacitance distribution detection circuit 92 includes a driver 95. The driver 95 applies a voltage to the drive lines HL1 to HLM in accordance with a code sequence, to drive the capacitors C11 to CMM. The capacitance distribution detection circuit 92 includes a sense amplifier 96. The sense amplifier 96 reads out, via the sense lines VL1 to VLM, a linear sum of voltages corresponding to the capacitors C11 to CMM driven by the driver 95, and supplies this linear sum of voltages to an A/D converter 98. The A/D converter 98 converts, from analog to digital, the linear sum of voltages corresponding to the capacitors, read out via the sense lines VL1 to VLM, and supplies the converted linear sum to a capacitance distribution calculation section 99.
The capacitance distribution calculation section 99 calculates a capacitance distribution on the touch panel 93 based on (i) the linear sum of voltages corresponding to the capacitors, supplied from the A/D converter 98, and (ii) the code sequence, and supplies the calculation result to a touch recognition section 90. The touch recognition section 90 recognizes a position touched on the touch panel 93 based on the capacitance distribution supplied from the capacitance distribution calculation section 99.
The capacitance distribution detection circuit 92 includes a timing generator 97. The timing generator 97 generates a signal specifying an operation of the driver 95, a signal specifying an operation of the sense amplifier 96, and a signal specifying an operation of the A/D converter 98, and supplies these signals to the driver 95, the sense amplifier 96, and the A/D converter 98, respectively.